Coma star cluster
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The Coma Cluster in Coma Berenices, designated Melotte 111 after its entry in the catalogue of deep sky objects by P. J. Melotte, is a small but nearby star cluster in our galaxy, containing about 40 stars (magnitude 5 to 10) with a common proper motion. It used to be known to represent Leo's tail, but Ptolemy III, in around 240 BC, renamed it for the Egyptian queen Berenice's sacrifice of her hair in a legend. The open cluster has a distance of 260 light years - almost as near as the Hyades - and covers an area of more than 5 degrees on the sky. In the FOV of a good field glass most of its stars can be seen simultaneously.
Below are 2 images of Melotte 111, taken from a rural location in Derbyshire, United Kingdom in March 2003, exposed for about 30 seconds with a normal film camera. The brighter stars of the cluster make out a distinctive "V" shape as seen when Coma Berenices is rising. The slightly orange background is caused by light pollution coming from nearby cities. The right hand image is the same photo with labels added. The position of Gamma Comae Berenices is shown, as are the constellation outlines (orange), constellation boundaries (blue), and lines of equal right ascension and declination (green).
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